The word `question` as used in this specification is intended to include any statement, which may be a statement in symbolic form, to which there are a plurality of responses. The word `answer` is intended to include any such response for example, true, false; yes, no; less than, equal to, greater than.
Many situations can be described by the answers to a series of questions. There may be many questions in the series and hence a large number of ways in which the answers can be combined in a set having one answer to each question. Associated with each set of answers there may be an instruction concerning the action to be taken in the situation described by that set of answers. The questions, sets of answers and instructions can be presented in a decision table in which the questions are arranged, for example, in a column and the answers are arranged in an array adjacent the column of questions, each column of the array being unique and corresponding to a unique set of answers. The instructions are associated with the columns of the array of answers. A person wishing to use the decision table to assist him in choosing the action to be taken in a situation must first describe the situation by a set of answers to the questions of the decision table. He must then search through the array of answers to find the column which corresponds to that set and hence the associated instruction. The invention provides an apparatus to assist in the search through the array.
According to the invention in a first aspect there is provided a method for determining the result of answers to a set of related questions each having at least two answers, wherein for all the questions respective answer devices are operated to present, in accordance with answers selected by the operator, answer symbols forming part of an array, the presented answer symbol or symbols associated with each question being disposed in a line of the array, all the presented symbols defining not more than one complete path through the array which leads the operator to a single reference out of a set of references carried by a record member.
According to the invention in a second aspect there is provided apparatus for determining the result of answers to a set of related questions each having at least two answers, comprising, for every question, an answer device which is operable to present, in accordance with answers selected by the operator, answer symbols forming part of an array, the presented answer symbol or symbols associated with each question being disposed in a line of the array, all the presented symbols defining not more than one complete path through the array which leads the operator to a single reference out of a set of references carried by a record member.